The 1986 Immigration Reform and Control Act - IRCA, or the Simpson-Mazzoli bill - is referred to frequently in today's high-decibel immigration debates - and rarely affectionately. As co-authors of that legislation, we think honest perspective is in order.

Today's tough issues are the same as when we chaired our respective immigration subcommittees: controlling illegal entry, the question of what to do with existing undocumented, illegal immigrants, and guest worker programs.

Our effort to craft responsible reform legislation was assisted by the well-documented recommendations of the bipartisan Commission on Immigration Reform, under the capable chairmanship of the Rev. Theodore Hesburgh, then President of Notre Dame University.

We knew that enacting an immigration reform law would require a bipartisan effort. We were Democratic and Republican - a good start. We held unprecedented joint House-Senate hearings - not just in Washington but all over the country. We heard from all sides and points of view.

We quickly realized that if immigration reform was to work and be fair it had to be a "three-legged stool." If one leg failed, so would the entire bill.

"Leg one" was improved security against illegal crossings at the border with Mexico, using the best available technology and additional, better-trained personnel. For the first time in U. S. history, we imposed penalties on employers who knowingly hired undocumented workers.

"Leg two" was the H-2A temporary worker program for agricultural workers, designed to ensure wage and workplace protections, and not to be another exploitative "bracero" program.

"Leg three" was what we called "legalization." We would allow some, but not all, undocumented aliens then living and working here to regularize their unlawful status and begin the long process to earn temporary residency and, eventually, if they chose to continue, to earn permanent residency and citizenship.

Since illegal immigration continues nearly unabated today, legitimate questions can be raised about the effectiveness of IRCA. Although we do have pride of authorship, we also believe that the shortcomings of the act are not due to design failure but rather to the failure of both Democratic and Republican administrations since 1986 to execute the law properly.

Not surprisingly, 20 years after the enactment of Simpson-Mazzoli, the Senate has passed an immigration reform bill composed of three main elements that are modified versions of the three legs of our bill: border security and workplace enforcement, a temporary worker program and legalization.

Would the Senate, knowing IRCA's track record, have settled upon our basic framework for its 2006 bill if IRCA was fatally flawed? We doubt it. From 1981, when our bill was introduced, to 1986, when it became law, we were aided by the expertise of hundreds of policy experts, scholars and advocates. Our comprehensive bill was crafted to curtail illegal immigration, to provide personnel for labor-scarce markets and to give the most worthy of our illegal population a chance to earn legal status.

The foundation of IRCA was enforcement and border security, but to work, it required consistent funding: for agents to investigate workplace violations, for prosecution of employers who broke the law, for more Border Patrol agents, and for installing the latest in high-tech monitoring and surveillance equipment. We saw the need for funding to develop a simple, reliable and tamper-proof system, a "more secure identifier," using cards or biometrics. Opponents from the right and the left savaged it as "a National ID," although it was not something that had to be carried on one-s person but was to be presented only at the time of "new hire" employment or when applying for government benefits.

After two decades, the system is still not in place. Unfortunately, what is in place is the use of several different identifiers, which were meant to be temporary, and a flourishing underground economy engaged in creating fraudulent documents for illegal immigrants.

All administrations since 1986 have allocated funding and personnel resources more generously to the task of securing the border than to enforcing IRCA in the workplace. Why? One answer is that there are never enough federal budget resources. Another is that administrations of both stripes are loathe to disrupt economic activities - i.e. labor supply in factories, farms and businesses. And we know that disruptions in the labor supply are the natural, unavoidable and even desirable consequence of strong border and workplace enforcement.

We believe that our three-legged-stool approach is still relevant and workable if carried out vigorously. We commend the Senate, which, in a worthy bipartisan effort, adopted such a framework this spring. The House bill is basically a tough "enforcement-only" measure.

We earnestly hope that before this Congress adjourns, the House and Senate will compromise, wring out the raw partisanship, and find a way to send President Bush - who has staked so much on enactment of solid immigration reform - a measure structured along the lines of our original bill. There is still time.

Romano L. Mazzoli was a Democratic representative from Kentucky. Alan K. Simpson was a Republican senator from Wyoming.